Sheet registering mechanism for printing machines



w. F. HUCK 2,231,914

SHEET REGISTERING MECHANISM FOR PRINTING MACHINES Feb. 18, 1941.

Original Filed Oct. 2, 193'! 8 Sheets-Sheet 1 INVENTOR M/L'lljdmfi'l'iucif. BY J g M TORNEY I E 0M1 w. F. HUCK 2,231,914

SHEET REGISTERING MECHANISM FOR PRINTING MACHINES Feb. 18, 1941.

'8 Sheets-Shin 2 Qriginal Filed Oct. 2, 1937 INVENTOR Feb. 18, 19-41. wuK 2,231,914

SHEET REGISTERING MECHANISM FOR PRINTING MACHINES Original Filed Oct. 2,19m 8 sheets-sheet 3 Feb. 18, 1941. w; E uc 2,231,914

SHEET REGISTERING MECHANISM FOR PRINTING MACHINES Original Filed Oct. 2,1937 8 Sheets-Sheet 4 mmvrox WLLuaJnF uclr.

ATTORNEY W. F. HUCK Feb. 18, 1941.

SHEET REGISTERING MECHANISM FOR PRINTING MACHINES Original Filed Oct. 2,1937 8 Sheeis-Sheeti W n m William F uclr.

Feb. 18, 1941. w K 2,231,914

SHEET REGISTERING MECHANISM FOR PRINTING MACHINES Origina1 Filed Oct. 2.1937 '8 Sheets-Sheet 6 INVENT OR William]? cir- ORNEY w. F. HUCK2,231,914

SHEET REGISTERING MECHANISM FOR PRINTING MACHINES Feb. 18, 1

8 Sheet s-Sheet 7 Original Filed Oct. 2, 193?! INVENT OR William EHucIr-A; TTORNEY PM Feb. 18,1941 I simmmicrsmm nan-mama ramrmomcnmss WilliamF.- mam nm. is. Y..

to B. Hoe l 00., Ina, notationalNewYol'k m ran, a. 1.1a eor- Applicationcoma-2.10:1. Martians f acclaim. (Crier-i114) r construction, as" wellas convenient, practical,

This invention relates to multi-color sheet fed rotary printing machinesand more particularly to a sheet feeding and registering mechanism forassociation and use with such machines whereby the sheets will be moreconveniently. expeditiously and accurately registered and fed to themachine.

It is particularly desirable that the sheets be accurately registeredupon a sheet carrying device before they are presented tov the printingunits of a multi-color printing machine, and to detect and strip fromthe sheet carrying device any sheets not properly registered. It isalsov desirable to provide means to actuate suitable. printing cylindercontrol mechanism, to separate the cooperating cylinders of eachprinting unit, when a sheet has been so stripped from the sheet carryingdevice and the said device is passing the respective printing unit.

One object of this invention is to provide a sheet feeding mechanismwhereby the above mentioned advantages will be obtained.

Another object'is to provide in a sheet feeding mechanism a sheetreceiving cylinder adapted to receive the sheets one at a time, and tolo- .cate them thereon in peripheral and axial register.

Another object is to provide means on a sheet receiving cylinder of theabove nature to detect misplaced sheets and which is adapted tosubsequently strip such sheets from the cylinder.

Still another object is to provide, in association'with a sheetreceiving cylinder of the above type, means to set a control means on asheet gripping device, when no sheet is received thereby, in conditionto actuate a printing cylinder tripping mechanism.

A further object is to provide a sheet receiving cylinder with means tohold the received sheet thereon and which is operable to locate thesheet axially thereon, while firmly holding it upon the periphery of thecylinder and mainvide a. sheet feeding and registering mechanism ofgenerally improved construction, whereby the same will be simple,durable, and inexpensive in serviceable and emcient in use.

with the foregoing and other objects in view, which will appear as thedescription proceeds, the invention resides ,in the combinations andarrangements of parts, and in the details of construction hereinafterdescribedand claimed.

The preferred embodiment of the invention is illustrated in theaccompanying drawings, wherein: 4

Figure 1 is a diagrammatic viewof a multicolor printing machine withwhich the sheet feeding mechanism of this invention may be associated; Vv f Figure 2 is a top plan view of a sheet receiving cylinder having thesheet feeding and registering mechanism of therewith; p

Figures 3, 4 and 5 are broken longitudinal sectional views ofthecylinder shown in Figure 2, each section being .a continuation ofanother. Certain parts are shown moved transversely from their truepositions to more clearly show their this invention associatedlongitudinal positions relatively to each other;

Figure 6 is a transverse section of the mechanism looking in thedirection of the arrows} in Flzurez;

Figure 8 is an enlarged partial section looking 1 in the direction ofthe arrows 8 in Figure 4;

. Figure9 is an enlarged partial transverse section of the cylinderlooking in the direction of the arrows 9 .in Figure 2; Figure l0 is atransverse section of the mechanism looking in thedirection of thearrows I0 in'Fi'gureZ;

- Figure llis a transverse section of the sheet gripping devicelookingin the direction of the arrows 'l I in Figure 3;

Figure 12 is an enlarged top plan view of one portion of the-sheetholding device; a Figure 13 is a section on line |3i3 of Figure 12; andt Figure 14 is an underneath view of part of the sheet holding devicelooking in the direction of the arrows in Figure 8. a

The sheet feeding and registering mechanism illustrated in the drawingsand which embodies the principles and novel features of this inventionincludes a conveyorand suitable guides to feed sheets one at a time tothe sheet transfer or receiving cylinder, sheet engaging stops on thecylinder to peripherally locate and register the sheets as they arereceived, means to axially locate and register the sheets on thecylinder, including a stop plate and an air pressure actuated sheetholding device which is adapted to draw the sheets taut and hold themfirmly upon the periphery of the cylinder, and a swingable fingeradapted to detect the presence of a sheet improperly located. Thedrawings also illustrate a sheet gripping device, suitable means on thecylinder to locate and register the sheet gripping device, camming meansto actuate the sheet gripping device to grip a sheet, cam Imeans actingon the sheet gripping device to insure it being positively located bythe locating and registering means, means actuated by the detectingfingers to release a sheet improperly located from the sheet grippingdevice and to striplit from the cylinder, and means to set a controlmember associated with the sheet gripping device and adapted to causethe printing cylinders to be tripped as the device is carried thereto byan endless conveyor chain or the like whereby actuation of the printingunit will be prevented when a sheet is not presented thereto. Suitablecontrol and actuating means are also illustrated, whereby all of theabove means and devices are actuated substantially automatically during'the rotative movement of the cylinder and in timed 2|, an impressioncylinder 22, and suitable inking relation to each other.

A printing machine, of the oil'set lithographic type, in which mechanismembodying the features of this invention is included, is illustrateddiagrammatically in Figure 1. Herein a sheet supply II is shown fromwhich sheets may be fed one at a time by a suitable sheet'feeding device|2 to a sheet receiving and transfer cylinder I3 over which a pluralityof sheet gripping devices are moved by spaced apart endless chains l4and by which they are carried successively to the printing units l5, l6,l1 and it, each of which may be adapted to print different coloredimpressions upon the sheets. Each of the printing units includes formand blanket cylinders l9 and and dampening mechanisms 23 and 24respective ly. Each printing unit is also provided with a well knownform of cylinder tripping mechanism indicated at 25 (in Figure 1), whichis adapted to be actuated by the engagement of a part, hereinconstituted by a roller 26, (shown in Figures 2 and 3, extending fromthe conveyor chain l4 and disposed in advance of a sheet grippingdevice), with a control finger 21 forming part of the cylinder trippingmechanism of each printing unit. After passing through the printingunits,

,thesheets are removed from the sheet gripping device and delivered to asuitable receiver 28, by a transfer belt or chain 29.

The sheet feeding device [2, illustrated in Figures 1 and 10, includesendless belts or tapes 3| running about suitable rollers 32 and 33 whichare driven from a sheet separating device (not shown) but which isassociated with the feeding device and with it is driven by the pressdrive.

Chains (not shown) are provided, having spaced apart guiding members 40thereon (see Figure 10) and these chains are arranged to be driven at aspeed slightly less than the tapes 3| and to run parallel therewith. Thepurpose of the mem- 'bers 40 is to engage the front edge of the sheetseparated from the pile and maintain it square on the tapes 3|. From theendless tapes 3|, the

sheets are directed onto a guide plate 4|.

I The guide plate 4| is adapted to 'direct the sheets upwardly and inunder a plurality of endless belts or tapes 42. and between them and thecylinder l4. Both the tapes ll and the tapes- 42 are driven at surfacespeed slightly faster than the peripheral surface speed of the cylinderl3 whereby the forward edge of the sheets being fed is pushed firmlyagainst a series of stops 4! (see Figures 3, 4, 5 and 9) extendingoutwardly from the periphery of the cylinder i3 andwhich are spacedapart at regular intervals lengthwise of the cylinder .(see Figure 2).The tapes 42 are driven from the large gear 36 by the pinions 34 and 44(see Figure 6) secured on the shafts of the rollers 48 and 41respectively, over which the belts 42 are led. The large gear 35 isconnected to the shaft 24 of the cylinder II which is driven from avertical shaft 31 (see Figure 5) through bevel gears 34 and It, theshaft 31 being understood to be drivingly connected to a common sourceof powerfor the printing units and driven in timed relation thereto.

The engagement of the forward edge of the sheet with the stops 4!locates each of the sheets on the cylinder It in a predeterminedposition on its periphery as they are fed thereto by the tapes 3|; thetapes 42, due to running slightly faster than the cylinder firmlyholding the sheets against the stops 42 after they have passed away fromthe influence of the pusher members 40.

A pair of oppositely directed and axially aligned bars 48 and 4! areslidably mounted between a pair of gibs ii and 52 secured in alongitudinally directed slot provided in and extending the length of thecylinder l3 and suitably spaced rearwardly of the stops 43 in respect tothe rotating direction of the cylinder ll (see Figures 2, 12 and 13).Each bar 48 and 49 is mounted upon and secured to a slide 83 whichslides are slidably mounted,

the cylinder to permit it sliding in either direction, plates II beingprovided at each end of the slides 53 to retain the bearing balls 54 inplace.

The bars 48 and 49 are each provided with a v plurality of counterboardopenings 56 in which spring pressed rotatable valve stems 51 aredisposed. The valve stems 51 have an enlarged headed end between whichand the shoulder 59, formed by the counterbore portion of the opening54, a coiled spring 6| reacts to maintain the head end I. firmly againstthe upper surface of the slide 54. Each valve stem has a central bore 62extending downwardly toward its headed end I8 and which is stopped shortof the extreme lower end of the stem and is adapted to be connected to alongitudinally extending groove 63 formed in the slide 53 by an openingor port 64 angularly disposed in respect to the axis of the bore 2. Atool receiving slot 65 is provided in the upper end of each valve stemby which the respective stem may be rotated to connect or disconnect theopening 64 with the groove 63 in the slide 53.

The grooves 63, in each slide, terminate at the opposing ends of theslides 53 and have a tube 66 extending therefrom into a sleeve 81 (seeFigure 4). The sleeve 81 is secured to. an adjacent and centrallydisposed cylinder part 12, herein comprising one of a plurality ofaxially spaced apart inwardly into connection with an opening 18extending inwardly from a face of the disc. A base block 19 of a valve,secured to the face of the disc 12, is provided with a port M inconnection with the opening 18 and with an arcuate recess 82 formed inthe face of the block 19 adjacent the disc 12. Another arcuate recess 83in opposed relation to the recess 82 is provided in the face of theblock 19 adjacent the disc 12 and is suitably connected, as by a pipe 84to a bore 85 formed in the cylinder shaft 38 (see Figure 3).

. and 94 provided in the face of the valve plate adjacent the block 19are adapted to bridge the openings 81 and 88 to connect the recesses 82and 83 whereby the vacuum-pump (not shown) may be connected to theopenings 52 in the stems 51 (see Figure 12),'disposed in the bars 48 and49, to cause the sheets to be firmly held on the cylinder' in theposition they have been located by the stops 43. I 7

An arm 95 (see Figures 9 and 10) is provided on the plate 89 and has aroller 96 journaled in .its free endadapted to be engaged between thethe cylinder I3 after spaced portions of the bifurcated end of an arm91. The arm 91 is secured to a rock shaft 98 which extends. from itsbearing in the disc 13 to and beyond the left hand end of the cylinderas 'viewed in Figures 3 and 4.

A arm 99 is secured upon the outer end of the shaft 98 (see Figures 3and 6). A roller II is journaled to the free end of the arm 99 and ridesupon the periphery of a plate cam I82 whereby the rock shaft will berocked at predetermined intervals. The cam I82 is secured as by bolts toone of "a pair of spaced apart supporting frame members I83 and I84 inwhich the cylinder shaft 35 is journaled as .by ball bearings I85.Rotation of the cylinder I3 upon its bearings I 85 will'cause the shaft98 to be rocked by the cam I82 which is properly formed to cause theabove described actuation of the valve parts to hold a sheet upon it hasbeen-engaged against the stops 43.

Spaced apart arms I88 and I81, one being located on either side of thearm 91, are secured to the rock shaft 98' (see Figures 4, 8 and 14).

' The arms I86 and I81 carry cam members I88,

I89. on their respective free ends. The camming edges III and H2 of themembers I88 and I89 I camming edges III and H2 are oppositely formedwhereby rocking movement of the shaft 98 will ,cause the slides 53 to beoppositely moved away from each other. 7

Due to their unequal overlap, the valve mem-- bergs will be slightlymoved before the valve ports are completely opened. As soon as the valvehas established a connection between a source of vacuum such as a vacuumpump and the movable slides 53, the sheet will be pressed by atmosphericpressure against the peripheral surface 'of'the cylinder. By havingfewer openings open or active, the sheet moving force of one bar, 48 or49, will overbalance that of the other, and the counteracting force'ofthe bar having the least number of openings 82 active, will impose astrain on the sheet and cause it to be straightened and stretched tautwhen the camming members I88 and I89 are actuated.

The arrangement shown is such that fewer openings 82 are in connectionwith the source of vacuum in the bar 49 than are so connected in the bar48, this being made possible by the structure of the stems 51 as abovedescribed, so that the sheet moving force of the bar 48 will overbalancethat of the bar 49, whereby the separating movement of these bars by thecam members I88 and I89 will cause the sheet to be slipped laterally, orlengthwise along the cylinder. I3, up against a stop bar II5 (seeFigures 2, 3, 7 and 12). The bar 5' is secured, as by screws, in apredetermined position upon and extended between a pair of spaced apartinverted T shaped bars H8 and H1 (Figures 12 and 13) slidably mounted insuitable slots I28, in gibs 52 and 5I respectively, one T shaped barbeing disposed on either side of the bar 48. Similar inverted T shapedbars H8 and H9 are provided in the gibs 5i and 52 (see Figure 2) anddisposed one on either side of the bar 49 should it be desirable to stopthe sheet in an opposite direction against a stop bar associated withthe bar 49; A plurality of spaced screw receiving threaded openings I2Iare provided in all of the T shaped bars and these openings are properlydisposed to permit the location of the stop bar H5 in proper position totransversely centralize the sheet upon the cylinder I3 and to laterallyregister it with the impressions to be printed thereon.

The slides 53, with the respective brackets II4 secured thereto, areeach constantly urged in a direction to insure constant contact of theroller II3, journaled in each bracket against the respective cam memberI88 and I89 by a spring I22 (see Figure 4). Each spring reacts betweenthe respective bracket II4 and a plate I23 secured to each of thesupporting discs II and 13. The inverted T shaped'bars H8, H9 areconstantly urged outwardly toward the respective end of the cylinder bysprings I24, one reacting between the inner end of each T bar and theend of the respective slot I28 in the gibs 5| and 52 (see Figure 12).

While the adjustment of the stop bar II 5 along the cylinder I3 isroughly made by use of the screw receiving threaded openings I2I a fineadjustment is made possible by the provision 'of a threaded rod I 25 incooperation with a threaded opening in the outer ends of each T shapedbar H8, H9 (see Figures '7 and 12). The outer ends of each of the rodsI25 has a pinion I26 secured thereto and theteeth of these pinions arein mesh with the teeth of a gear I21 journaled to an end plate I28. Atool engaging member or nut I29 is secured to each gear I 21 whereby itmay be rotated to actuate the rods I 25 and thereby simultaneously slidethe T shaped bars H8 and H1 or ill and H9 against the springs I 24 todelicately position the stop bar II 5 connected thereto.

Sheet gripping device and carrier Each of the sheetgripper devicesprovided on holders I32 and I33, one holder being suitably 1| connectedto each of the chains, which in turn are led over and driven by asprocket I34 secured to the shaft 38 at each end of the cylinder I3 (seeFigures. 2, 3, 4 and5). A smaller diameter tube I35 (see Figures 9 and10)'is disposed concentrically to, and in,the tube -I3I and also extendsacross the cylinder I3. The tube I351: arranged to be rotatablerelatively to the tube I 3|. A plurality of fingers I38 are secured tothe outer tube I31 and are spaced apart lengthwise thereof to agree withspaced apart fingers I31 secured to the inner tube I38. The fingers I31pass through. suitable openings I38 in the outer tube and are constantlyurged into closed engaging position with the fingers I38 by springs I3Each of the holders I32 and I33 are provided with a pair of rollers Iand I42, the roller I being joumaled in and between spaced apart linksI43 which are pivoted to the holders I32 and I33 at I44, and the rollerI42 being journaled to the respective holder at I45 (see Figures 6 and10). Another roller I48, herein shown of larger diameter than therollers HI and I42, is journaled to the holders I32 and I33substantially midway between the rollers HI and I42. The rollers I 48are adapted to ride on arcuately shaped two piece guides, portions I41and I48 constituting one guide and located at one end of the cylinder I3and portions I49 and I5I constituting the other guide and being locatedat the other end of thecylinder. Each of the portions I41 and I48 of oneguide are pivoted on eccentric studs I52 and I53 respectively to theadjacent machine frame I 83 and the portions I49 and I5I are pivoted onsimilar eccentric studs I52 and I53 respectively to the adjacent machineframe I04.

The guide portions I 41 and I49 are adjustable toward and away from theaxis of the cylinder I3 by means of ,their eccentric pivot stud I52 andby an adjusting screw I54, shown only in connection with guide I49,secured in the adjacent frame and being adapted to engage the free endof each-portion. The'guide portions I48 and I5I are resilientlypositioned by springs I55 which react between a shoulder formed at thefree end of each guide portion and a screw I58 adjustably secured in theadjacent frame. Stop screws I51 adjustably secured to the adjacent framelimit the inward movement of the guide portions I48 and I5I and theengagement of interengaglng abutting ends of the guide portions I41 andI48 and I49 and I5I between the eccentric studs I52 and I53 limit theinward movement of the portions I41 and I49.

The arrangement of the above parts is such that the rollers I48 on eachholder I32 and I33 cooperates with the guides I41, I48, I49 and I 5|respectively, the said guides extending more than 180 and beingsubstantially concentric with the axis of the cylinder I3 and disposedabove the same, to press the sheet gripping devices inwardly to causeengagement of the rollers I and I42 on each holder I32 and I33 with theends of a pair of plates I58 and I59 respectively. The plates I58 andI59 are secured to the inner face of each of the sprockets I34, that is,the faces thereof adjacent the cylinder end, one plate I58 of each pairbeing provided with a square end and the end of the other plate I59 ofeach pair being formed to provide aseat to receive the engaging roller.One of the plates I 58 is provided with an arcuate seat I8I while theother has a V shaped seat I82. The plate I88 having the v shaped seatI82 also has the edges of the v seat beveled as at I83 to fit a V shapedgroove I84 provided in the periphery of the cooperating 'roller' I42(see Figure 3). This arrangement insures both peripheral and transverseregister of the sheet gripping devices with the cylinder I3, each deviceas it approaches the cylinder being pressed into a suitable recessformed by cutting away the outer shell 18 of the cylinder-and sectionsof each disc 88, 88 and 1I--15 to permit entrance of the device therein.Suitably formed plates I85 (see Figures 4 and 9) are provided andsecured to each of the intermediate discs H and 13 to sup- Port roller,I18. adapted to engage the outer tube I3I and cause deflection of thetube outwardly so that the deflection due to centrifugal force will beanticipated and the tube be held steady.

An arm I88 secured to the inner tube I35 extends outwardly through anopening I81 provided in,the holder I33 and has a roller I88 jourv naledtherein (see Figures 5, 9 and 10). The roller I88 is adapted to engagethe inner edge of an arcuate plate cam I89 supported on brackets I" tothe adjacent frame member I84. The arm 188 when engaged by the cam plateI89 rocks the tube I and opens thegripper fingers bycausing swingingmovement of the fingers I31 away from the fingers I38. The cam plate I89is also disposed generally concentric with the axis of the cylinder I3and extends somewhat less than 180 thereover. The camming edge I12 ofthe cam plate I89 is formed to gradually open and close the fingers I38and I 31 and to insure that they are fully open substantially over themiddle portion of the plate I83. The plate is so disposed relatively tothe cylinder I3 that the fingers I38 and I31 will be fully closed upon asheet carried by the cylinder' before the chains I4 carrying thegripping devices ride of! of the respective sprockets I34 and before therollers I48 are released from the action of the guide portions I41 andI49 to insure that the sheet, now in register on the cylinder, will betransferred therefrom by the chain I4 and along with the grippingdevices, to and in perfect register with, the printing units I5-I8inclusive.

Misplaced or absent sheet detecting able position by the detection of asheet being misplaced or absent from the cylinder I3 by levers I13 and I14, a pair of which are herein shown in Figure 4 spaced apart lengthwiseof the-cylinder I3 and disposed one adjacent the disc H and the otheradjacent the disc 13. The

stops 43 are replaced at these points with a pair of elongated stops I15and I18, one of which is disposed on either side of each of the leversI13 and I14.

The levers I13 and I14 (see Figures 4 and 9) are formed with a narrowbody portion I11 having a substantially wider head portion I18 at itsouter end and has a cross bar I19 secured to its inner end. The leversI13 and I14 have a spindle I 8I secured to their body portions I11,which spindle has its ends Journaled in the stops I15 and I18. Thelevers I13 and I14 are preferably formed from sheet metal so as to be aslight in weight as possible and both the cross bar I18 and the spindleI8I are brazed or similarly secured thereto. The wider outer end, orhead portion I18, is adapted to freely pass between the outer ends ofthe stops I15 and I18 and is urged beyond the surface of these stops I15and I16, and of the stops 43 toward the sheet bein fed onto thecylinder, by a small leaf spring I82, a sumcient amount to be engaged bythe edge of this sheet before it engages the said stops. The leaf springI82 has one of its ends secured to the cylinder I3 while its other endengages the respective lever I13 or I14.

Normally each of the cross bars I19 are maintained by the springs I82 inthe path of a stop plate I 83 secured upon the free end of each of apair of arms I84, which are secured to a rock shaft I85 (see Figure 9).The shaft I35 extends from the lever I13 through the discs 1|, 12, 13,14 and 15 to the right hand end of the cylinder I3.

When a sheet has been fed onto the cylinder into proper engagement withthe stops 43, I15 and I16, the levers I13 and I14 are swung intoalignment with these stops against the tension of the springs I 82,whereby the cross bars I19 are moved out of the path of the plates I33thereby permitting movement of the arms I84, and consequently rockingmovement of the shaft I85. Thus the proper disposition of a sheet uponthe cylinder I3 and against the stops 43, I15 and I16 is detected. Anysheet which is misplaced on the cylinder, whereby its forward edge isnot in engagement with all of the stops 43, I15 and I16 will bedetected, as in such cases one or the other of the levers I13 and I14will not be swung to carry the cross-bar I19 thereon out of the path ofone of the stop plates I83, and thus rocking movement of the shaft I85is prevented. In like manner, absence of a sheet from the cylinder willcause failure of both of the levers I 13 and I14 to swing to carry thecross-bars I19 out of the path of the plates I83.

When the shaft I85 is prevented from rocking, due to the failure ofeither or both of the crossbars I19 to be moved out of the path of theplates I83,- a roller I86, joumaled in the free end of an arm I81 whichis secured to the end of the shaft I85 adjacent the right hand end ofthe cylinder I3 and disposed beyond the sprocket I34 thereat, isprevented from following down the camming edge I 88 of a plate cam I89which is secured, as by screws, to the frame I84 (see Figure Anotherroller I9 I, also carried by the arm I81, is therefore prevented frommoving out of the path of a long arm I92 of a cam lever I93 which ispivoted at I94 (see Figure 18) to the frame I84 and engages the lever torock it on its pivot I94 as the cylinder I3 rotates. The short arm I95of the lever I93 (see Figure is connected by a link I96 to an arm I91pivoted at I98 to an arm I99 secured to a rock shaft 28I. The shaft 28Iextends from one frame I83 to the other frame I84, being joumaled ateach end in each frame. The shaft I85 is constantly urged to rock in theproper direction to cause the roller I86 to follow the cam edge I88 by aspring I88, which reacts between an arm I98 on the shaft I85 and a stud288 (see Figures 5 and 9) secured to the disc 14. A coiled spring 282(see Figure 10) is provided to normally maintain the lever I53 in itsroller "I engaging position by reacting between a lug 283 on the frameI84 and a stud 284 pivoted on the free end of the lever short arm I95.

The spring 282 acting on the lever short arm I 95 also maintains a catchpin 285, provided on the free end of the arm I91 out of proper posiitionto be engaged by a catch 286 carried by a bifurcated arm 281 securedupon one end of a shortsshaft 288 journaled in the frame I84 (seeFigures 5 and 18). Another arm 288, secured upon the other end of theshaft 288, carries a roller 2I8 which rides upon the camming edge 2I2 ofa plate cam 2I3. upon the hub 2 of the large bevel gear 38, se-

cured upon the end of the cylinder shaft 36. A coiled spring 2I5reacting between an arm 2I6 secured on the shaft 288 and a stud 2"connected to the frame I84 maintains the roller 2I8 in constant contactwith the cam 2I3 whereby the shaft 288 is being continuously rocked toswing the catch 286 to and fro. The catch 286 will engage the pin 285when the latter is lowered, due to the downward swinging of the arm I91through the link I96 by swinging movement of the lever I93 induced bythe engagement of the roller I9I with the long arm I92 of said lever.Engagement of the pin 285 by the catch 286 will, through the arm I91,cause the arm I 99 to be rocked to rock the shaft 28I.

Rocking movement of the arm I99 as herein shown, toward the cylinder I3(see Figure 10) will, as above described, rock the shaft 28I whereby anarm 2I8 secured upon the end of said shaft adjacent the frame I84 willbe rocked to present a cam block 2I9 carried thereby in position to beengaged by the roller I68, carried by the holder I33, whereby the sheetgripping fingers I36 and I31 will be opened to release a sheet, shouldone be gripped thereby. At the same time the fingers I36 and I31 open, aplurality of stripper fingers 22I of a form as shown in Figure 2 and indotted lines in Figure 10 and which are spaced apart along the shaft 28Iand connected thereto, as by screws at their lower ends, are swungtoward the cylinder I3 to become disposed beneath the sheet, if any,being carried by said fingers to strip such sheet from both the fingersand the cylinder. The rocked shaft 28I, the arm I99, the cam block 2I9and the stripper fingers 22 I are returned after actuation as abovedescribed and are normally maintained, unless so actuated, by coiledsprings 222 reacting between 9. lug 223 on the frames I83 and I84 andarms 224 secured to the shaft 28I.

. Printing unit tripping arrangement Referring back to the roller 26 onthe gripper device and which as described is adapted when properly setto trip the cylinders of the printing units as it passes thereby, asleeve 225 is provided which is rotatably mounted upon the outer tubeI3I and has a plurality of pairs of spaced apart ears 226, 221, 228 and229, and to and between each pair of ears, rollers, 26, 23I, 232 and 233are respectively disposed and iournaled (see Figures 3, 6 and 11). Aspring pressed pin 234 ccoperates with the roller 23I to maintain thesleeve 225 in either of its rotative positions to which it may be movedrelatively to the tube II. The rollers 23I and 232 are axially spacedfrom the rollers 26 and 233, with the roller 232 disposed to engage acam block 235 mounted on an arm 235 connected to the shaft 28I.

The arrangement is such that when a gripping device passes the cam block235 and said cam The cam 2I3 is secured block has been rocked inwardlytoward the cylinder I3 due to the rocking movement of the shaft 20I asabove described, the sleeve 225 will be rotated about the tube I3I, asshown in dotted lines in Figure 11. The roller 23I will then be diaaosedon the other side of the.pin 234 and the roller 26 will be disposedoutwardly a sumcient amount to insure it engaging with the actuating andcontrol finger 21 of the tripping mechanism 25 at each printing unit, toactuate the same to prevent the printing cylinders engaging. After thesheet gripping device, so set, has passed by the sheet receiving device28 a suitable cam block or the like (not shown) but suitably positionedto engage the roller 233, will reset the sleeve 225 into its normalposition wherein it will be maintained by the cooperating pin 234 andthe roller 23I. Suitable chain guides 231 are provided at each end ofthe cylinder I3 to be engaged by and to brace the chain l4 passingthereby, whenever the cam blocks 2 I 9 and 235 are disposed to open thegrip er fingers I36 and I31 and to rock the sleeve 225 respectively, asabove described.

Provision is made of means to manually actuate the lever I93 to set theprinting unit tripping roller 26 and to strip a sheet from the cylinderI3. This means includes a link 238 connected to so the lever I93 at 239(see Figure and to a lever arm 2 secured to a stud shaft 242, whichextends through the frame I04 and has a handle 243 secured thereto.Suitable actuation of the handle 243 will cause the above mentionedactions to take place.

Operation The detail operations of the several portions of the sheetfeeding and registering mechanism of 0 this invention have beendescribed in connection with the above description of the parts thereof.The sequence in which these operations are performed by the mechanism iscontrolled by the controlling and actuating cams I02, I08, I09, I69, 45I89 and 2I3 together with the gear and chain drives associated with thevarious parts, the cams being formed and driven in timed relation withthe endless chain I4, carrying the sheet gripping mechanisms, and withthe drive gears 50 38, 39, 35, 34 and 44. As referred to above, thesheets are fed one at a time by suitable means,

including the endless tapes 3| and cooperating sheet pushing members 40,and are driven slightly faster than the cylinder I3, upon and along 55the guide plate 4I, which directs the sheets upwardly upon the cylinderI3 beneath the endless tapes 42. The feeding of the sheets upon thecylinder I3 is timed by suitable gear connections 34, 35 and 44 so thatthe forward edge of the 60 sheet reaches the cylinder in time to engageagainst the stops 43, and due to the faster rate of speed of the tapes42 is constantly urged thereagainst.

As the cylinder I3 is continuously rotating, the 155 sheet edge, firmlypressed against the stops 43, moves forward with the cylinder, and atthe same time one of the plurality of sheet gripping devices carried onthe endless chain I4 is in the recess provided therefor in the cylinder,and is 7 directly in advance of the stops 43, with the sheet grippingfingers I36 and I31 thereof in open position, the roller controlling thefinger I31 having become engaged by the plate cam I69. The sheetgripping devices are also being held in this recess 7 by the engagementof the large rollers I46 with the guides I41, I48, I49 and I5I and beingaccurately located on the cylinder by the cooperating beveled edges I63of the V shaped seat I62 and grooves I64 in the plate I59 and the rollerI42 respectively. I!

As soon as the cylinder I3 has advanced sufficiently for the sheet tooverlie the sheet holding bars 48. and 49, the valve plate 89 is rotatedby the cam I02 to connect the openings 56 with the vacuum pump (notshown), the bars 48 and 49 1 slightly subsequent to this action, beingstarted to slide in opposite directions by the camming members I08 andI09. Pressure now being applied to the sheet to hold it upon the bars 48and 49, more firmly to one than to the other, causes the sheet to beslipped transversely, or axially in respect to the cylinder I3, toengage one of its edges against the stop bar II5. Continued rotation ofthe cylinder I3 advances the sheet held thereon by the tapes 42 againstthe stops 43, and by air pressure upon the bars 48 and 49 which in turn,due to their oppositely directed movements have drawn the sheet tautwith one edge engaging the stop bar II5, to a position whereat thefingers I31 are released from the opening action of the cam I69 and theyclose with the fingers I36 to firmly grip a sheet therebetween.

The sheet, now accurately in register, is carried along by the sheetgripping mechanism in timed relation, due to the chain drive I4, whichhas meanwhile followed over the sprockets I34, and is driven thereby,due to their connection with the bevel gears 38 and 39, to the printingunits I5-I8, with which the vertical bevel gear 85 shaft 31 is connectedin the usual manner. As the sheets pass through the printing units,impressions in color may be printed thereon with the difi'erent colorfrom each printing unit being accurately in register with the others.After 40 passing the last printing unit I8, the printed sheet may betransferred to the delivery belt or chain 29 and deposited at thereceiving device 28.

Should the detector fingers detect the absence 4 of a sheet or thepresence of a sheet misplaced, or improperly in engagement with thestops 43, the cams I89, I93 and 2I3 are automatically brought intoaction to open the fingers I36 and I31, to strip the misplaced sheetfrom the cylinder I3, and to set the roller 26 in position to trip themechanism 25 at each printing unit, to prevent the printing cylindersfrom contacting, while the sheetless sheet gripping mechanism passesthereby, all as above described in the above description of the partsthereof.

It will be understood that the invention may be embodied in otherspecific forms without departing from the spirit or essential attributesthereof, and it is therefore desired that the present embodiment beconsidered in all respects as illustrative and not restrictive, and itwill be further understood that each and every novel feature andcombination present in, or possessed by, the mechanism herein disclosedforms a part of the invention included in this application.

What I claim is:

1. In a sheet feeding and registering mechanism for a printing machine,a continuously rotating cylinder, means to feed a sheet to saidcylinder, 9. stop on said cylinder against which the forward edge of thesheet is pressed by said feeding means, a stop bar on said cylinderadjacent one of its ends, sheet holding means slidable axially of saidcylinder to press a side edge (6 scrapie I of the sheet against saidstop bar,

said fingers are mounted to carry the finger gripped sheet from saidcylinder.

2. In a sheet feeding and registering mechanism for a printing machine.a continuously rotating cylinder, means to feed a sheet to saidcylinder, 9. stop on said cylinder against which the forward edge of thesheet .is pressed'by said feeding means, a stop bar on said cylinder adsjacent one of its ends, sheet holding meansslidable axially of saidcylinder to press a sideedge of the sheet against said stop bar. a sheetgripping and carrying device having sheet gripping I fingers, andmembers on said cylinder and engageablc by said device to locate itrelatively to said cylinder and to the sheet thereon.

3. In a sheet feeding and registering mechanism for a printing machine,a continuously rotating cylinder, means to feed a sheet to saidcylinder, a stop on said cylinder against'which the forward edge of thesheet is pressed by said feeding means, a stop bar on said cylinderadjacent one of its ends, sheet holding means slidable axially of saidcylinder to press a side edge of the sheet against said stop bar, amisplaced or absent sheet detector associated with said stop, operablesheet gripping fingers, andcooperating members between said fingers andsaid detector and actuated by said detector to open said fingers. v

4. In asheet feeding and registering mechanism for aprinting machine, acontinuously rotating cylinder, means to feed a sheet to said cylinder,a stop on said cylinder against which the forward edge of the sheet ispressed bysaid feeding means, a stop bar on said cylinder adjacent oneof its ends, sheet holding means-slidable' axially of said cylinder topress a side edge of the sheet against said stop bar, a sheet printingunit having a control finger, a misplaced -or' absent sheet detectorassociated with said stop, a sheet gripping and conveying device, and acon trol finger tripping member on said sheet conveying device adaptedto be set by said detector,

.to trip said control finger.

5. In a sheet feeding and registering mechanism for a printing machine,a continuously'rotating cylinder, means to feed a sheet to saidcylinder, a stop .on said cylinder against which the forward edge of thesheet is pressed by said feeding means, a stop bar on said cylinderadjacent one of its ends, sheet holding means slidable axially of saidcylinder to press a side edge of the sheet against said stop bar, asheet gripping and carrying device having sheet gripping fingers,members on said cylinder and engageable by said device to locate itrelatively to said cylin der and to the sheet thereon, a misplaced orabsent sheet detector associated with said stop, and cooperating membersbetween said-fingers and said detector and actuated by said detector toopensaid fingers. I

6. Ina sheet feeding and registering mechanism for a printing machine, acontinuously rotating cylinder, a sheet stop against which a sheet fedto said cylinder will. engage, a sheet gripping device on said cylinderin advance of said sheet stop, a sheet holding device on said cylinderto the rear of said sheet stop, said sheet holding device includingoppositely. movable sheet holding members adapted to move axially ofsaid cylinder, and a continuously running belt to engage a sheet andconstantly press it against said a... while said sheet holding device isin operation.

r. m a sheet feeding and registering mechatating cylinder. a sheet stopagainst which a sheet fed to said cylinder will engage, a sheet n ppindevice on said cylinder in advance of said sheet stop, a sheet holdingdevice on said cylinder to V nismfor a printing machine, a continuouslyro-.

the rear of said sheet stop. said sheet holdins device includingoppositely movable sheet holding members adapted to move axially of saidcylinder, a cam to move each sheet holding member to draw a sheet tautaxially of said cylinder, a stop bar, adjacent an end of said cylinder,said sheet holding members being adapted to draw an edge of a sheetagainst said stop bar, and a 'con- .device on said cylinder in advanceof said sheet stop, a sheet holding device on said cylinder to the rearof said sheet stop, said sheet holding device including oppositelymovable sheet holding members adapted to move axially of said cylinder,a continuously running belt to engage a sheet and constantly press itagainst said stop while said sheet holding device is in operation, asheet edge engaging member associated with said stop, and a sheetstripping member adapted to be actuated by said sheet edge engagingmember to strip a misplaced sheet from said cylinder.

9. In a sheet registering mechanism, a rotat-. ing cylinder having asheet edge engaging stop thereon, a running 'belt to press a sheetagainst the cylinder and an edge of the sheet against said stop, amember operable to strip a sheet from ,said cylinder, and a member toactuate said sheet stop, sheet gripping members associated with saidcylinder including closable and openable sheet gripping fingers, amember operable to strip a sheet from said cylinder after it has beengripped by said fingers, and a member to open said fingers and toactuate said sheet stripping member controlled by a sheet pressed towardsaid stop by said belt.

11. In a sheet registering mechanism, a rotating cylinder having a sheetedge engaging stop thereon, arunning belt to press a sheet against thecylinder and an edge of the sheet against said stop, a stop bar disposedon and adjacent an end of said cylinder, sheet holding members operableto slippingly hold a sheetand to press an edge thereof against said stopbar, sheet gripping members associated with said cylinder includingclosable and openable sheet gripping fingers, a member operable to stripa sheet from said cylindex after it has been gripped by said fingers,and a member to open said fingers and to actuate said sheet strippingmember controlled by a sheet pressed toward said stop by said belt.

12. In a combined sheet transferring and registering cylinder, means torotate said cylinder,

a stop on said cylinder to engage the forward end of a sheet feed ontosaid cylinder, a stop bar on and adjacent to one end of said cylinder,sheet holding means associated with said stop bar andadaptedtopressasideedgeofthesheetthereagainst, sheet gripping fingersmounted on a carrier, said carrier being adapted to rotate about theaxis of and with said cylinder'a portion of one revolution of saidcylinder, and cooperating members associated with said cylinder toregister said carrier with said stop while said carrier is rotating withsaid cylinder.

13. In a combined sheet transferring and registering cylinder, means torotate said cylinder, 9. stop on said cylinder to engage the forward'end of a sheet fed onto said cylinder, sheet grip-' ping fingersmounted on a carrier, said carrier being adapted to rotate about theaxis of and with said cylinder a portion of one revolution of saidcylinder and then to convey a sheet away from said cylinder,and'cooperating members associated with said cylinder to register saidcarrier with said stop while said carrier'is rotating with saidcylinder.

14. In combination, a rotating cylinder, a plurality of stops disposedin alignment axially across said cylinder, a running" belt adapted tofeed a sheet onto said cylinder and an edge of the sheet against saidstops, a stop bar adjacent one end of said cylinder, oppositely movablesheet holding members adapted to maintain another sheet edge againstsaid stop ban-sheet ripping mechanism adapted to be associated with saidcylinder during a portion of one revolution of said cylinder, andcooperating members between said mechanism and said cylinder to registersaid,

mechanism with the sheet as held .against said stops and said stop bar.

15. In combination, a rotating cylinder, a plurality of ,stops disposedin alignment axially across said cylinder, a running belt adapted tofeed a sheet onto said cylinder and an edge of the sheet against saidstops, a stop bar adja- 40 cent one end of said cylinder, oppositelymovable sheetholding members adapted to maintain another sheet edgeagainst said stop bar, sheet gripping mechanism adapted to be associatedwith said cylinder during a portion ofone revolution 01' said cylinder,said mechanism having a member adapted to be set in position to operatea trip mechanism associated with a printing unit to which said sheetgripping mechanism is carried after leaving said cylinder, means actedupon by the sheet to prevent said member becoming set in trip mechanismactuating position, andcooperating members between said mechanism andsaid cylinder to register said mechanism with the sheet as held againstsaid stops and said stop bar.

16. In combination, a rotating cylinder, a plurality of stops disposedin alignment axially across said cylinder, a running belt adapted tofeed a sheet onto said cylinder and an edge of the sheet against saidstops, sheet gripping mechanism adapted to be associated with saidcylinder during a portion of one revolution of said cylinder,cooperating members on said cylinder and on said mechanism to registersaid mechanism with said stops, said mechanism having a 5 member adaptedto be set in a position to actuate a trip mechanism at a position remotefrom said cylinder, means acted upon by the sheet edge against saidstops to prevent the setting of said member, and cooperating membersbetween said sheet gripping mechanism and said cylinder to register saidsheet ripping mechanism with the sheet as held against said stops andsaid stop bar.

17. In a printing machine having an impression'cylinder, sheet feedingmeans including a ceivable in the cylinder opening, means toregisrotatable sheet registering cylinder having an opening in itsperiphery, sheet gripping mechanism adapted to rotate with saidregistering cylinder while disposed in the opening therein and to carrythe sheet from the cylinder, sheet stops 5 arranged to .be engaged by asheet fed to said registering cylinder whereby the sheet will beregistered in respect to said sheet gripping mechanism, and means toactuate said sheet gripping mechanism after a sheet is against saidstops. 1o 18. In combination with a printing machine, sheet feedingmeans including a rotatable sheet registering cylinder having an openingin its periphery, a plurality oi sheet gripping mechanisms adapted torotate with said cylinder while being 15 successively disposed intheopening and to carry sheets therefrom to a printing cylinder, sheetstops arranged to be engaged by each sheet fed onto said registeringcylinder whereby the sheet will'beregistered in respect to said sheetgripping 20 mechanism, means to actuate each sheet gripping mechanismafter a sheet is against said stops, and means to detect the failure ofa sheet to engage said stops and to prevent the sheet-being carried fromsaid cylinder by said gripper mechanism. 19. In combination with aprinting machine, a flexible sheet conveyor and a rotatable cylinderhaving an opening in its periphery, sheet gripping mechanism carried bysaid conveyor and reter and secure said mechanism in the openingwhilethe cylinder is rotating, sheet registering stops adapted to beengaged by a sheet received on said cylinder, and sheet feeding meansadapted to feed a sheet to said cylinder and hold it 35 against saidstops before said sheet gripping mechanism is actuated to grip thesheet.

20. In combination with a printing machine, a flexible sheet conveyorand a rotatable cylinder havingan opening in its periphery, sheetgripping 40 mechanism carried by said conveyor and receivable in thecylinder opening, means to register and secure said mechanism in theopening while the cylinder is rotating, sheet registering stops adapted.to be engaged by a sheet received on said cylinder, sheet feeding meansadapted to feed a sheet to said cylinder and hold it against said stopsbefore said sheet gripping mechanism is actuated to grip a sheet, meansto actuate said gripping mechanism to release a sheet gripped thereby,and means actuated by a sheet properly disposed against one of saidstops to prevent actuation of said gripper mechanism releasing means.

21. A rotatable sheet receivingand registering cylinder adapted fordisposition between a sheet feeding mechanism and a printing unit of aprinting machine, said cylinder having an opening to receive a sheetgripping mechanism carried thereabout by a conveyor and having means toso register said gripper mechanism thereon, and stops carried by saidcylinder to be engaged by a sheet to register it peripherally andaxially on said cylinder before said gripper mechanism is actuated togrip the sheet. 65

22. A rotatable sheet receiving and registering cylinder adapted -fordisposition between a sheet feeding mechanism and a printing unit of aprinting machine, said cylinder having an opening to receive a sheetgripping mechanism carried there-' about by a conveyor and having meansto register said gripper mechanism thereon, stop's carried by saidcylinder to be engaged byv a sheet to register, it peripherally andaxially on said cylinder before said gripper mechanism is actuated togrip a 75 means to feed a sheet to 'said registering cylinder sheet, anda sheet register detector mechanism carried by said cylinder inassociation with one of said stops and adapted to cause actuation of adevice to release a sheet from said gripper mechanism as it leaves saidcylinder.

23. In combination with a printing machine having a printing cylindertripping mechanism.

associated with one of its printing units, a sheet tion to actuate saidprinting cylinder tripping mechanism as said member approaches the same,means on said cylinder to register a sheet disposed thereon, and a sheetregister detecting member on said cylinder actuated by a sheet receivedthereon to prevent the setting of said tripping member in trippingposition.

24. In a printing machine, a rotating cylinder, sheet grippers movingtherewith and operable to grip a sheet fed to said cylinder, means tofeed a sheet to said cylinder at a higher speed than the peripheralspeed thereof, a side registering stop positioned to register aside edgeof the sheet on the cylinder, sheet moving means on the cylinder to movethe sheet against the stop, and means to actuate the grippers to engagethe sheet after the sheet has been moved against thestop.

25. In a printing machine having an impression I cylinder, a sheetregistering cylinder having sheet grippers moving therewith and operableto grip a sheet fed to said registering cylinder and to carry the sheetfrom the registering cylinder,

at a higher speed than the peripheral speed thereof, a plurality ofsheet registering stops positioned to register the forward edge of thesheet on the registering cylinder, sheet moving means .operating fasterthan the peripheral speed of the registering cylinder to move the sheetagainst the stops, and means to actuate the grippers to engage the sheetafter the sheet has been moved against the stops.

26. In a printing machine having an impression cylinder, a sheetregistering cylinder having a sheet'gripping member carried by saidregistering cylinder as it rotates and being operable to grip a sheetdisposed on said registering cylinder and to carry the sheet from theregistering cylinder, means to feed a sheet to the registering cylinder,a sheet registering stop carried by said registering cylinder, sheetmoving means to move the sheet against said stop, and means to actuatesaid sheet gripping member after a sheet has been moved against thestop.

27. In a printing machine, a rotatable cylinder, a sheet gripping membercarried by said cylinder as it rotates and being operable to grip asheet disposed on said cylinder and to carry the sheet from thecylinder, means to feed a sheet to the .cylinder, a sheet registeringstop carried by said cylinder for engaging the forward edge of thesheet, a sheet side registering stop carried by saidcylinder, means tomove the sheet forwardly against the forward stop and transverselyagainst the side stop, and means to actuate said sheet gripping memberto grip a sheet positioned against said stops.

28. In combination, a sheet registering cylinder and a sheet feedingmember rotatable therewith,

operable sheet gripping fingers carried by said member, means to strip asheet from said feeding member, and means to open said fingers andactuate said sheet stripping means when a sheet is misplaced in respectto said sheet feeding member. 29. In a sheet feeding mechanism, a sheetregistering cylinder, releasable sheet engaging means rotatable with thecylinder and adapted to feed a sheet, and means to engage a sheetimproperly disposed in respect to said sheet engaging means and toremove it from said mechanism. 30. In a sheet feeding mechanism, a sheetregistering cylinder, releasable sheet engaging means rotatable with thecylinder and adapted to feed a sheet, means to engage a sheet improperlydisposed in respect to said sheet engaging means and to remove it fromsaid mechanism, and means actuated by a sheet properly disposed toprevent operation of said sheet removing means.

31. In a printing machine having a plurality of printing cylinders andmeans for tripping them on" and 01! impression, a sheet feeder, aflexible sheet conveyor having a pluralityof relatively spaced sheetcarriers each adapted to receive a sheet, a rotating member about whichthe sheet conveyor runs and which is arranged to guide each sheetcarrier successively past a position where it may receive a sheet fromthe feeder, said conveyor being arranged to convey the sheetssucessively past each printing cylinder, a sheet detector in the path ofsheets presented to'the sheet carriers and operable by a misregisteredsheet, and means on the conveyor operated by said detector to actuatethe tripping mechanism of each of the printing cylinders in succession,on the approach'of a sheet carrier to which a misregistered sheet waspresented.

32. In a printing machine having a plurality of printing cylinders andmeans for tripping themon and o impression, a sheet feeder, a flexiwhereit may receive a sheet from the feeder, said conveyor being arranged toconvey the sheets successively past each printing cylinder, a sheetdetector associated with the said rotating member and operable by amisregistered sheet, and means on the conveyor operated-by said detectorto actuate the tripping mechanism of each of the printing cylinders insuccession, on the approach of a sheet carrier to which a misregisteredsheet was presented.

33. In a printing machine having a plurality of printing couples andmeans for tripping them on" and off" impression, a sheet feeder, a

flexible sheet conveyor having a plurality of relatively spaced sheetcarriers each adapted to receive a sheet, a rotating member about whichthe sheet'conveyor runs and which is arranged to guide each sheetcarrier successively past a position where it may receive a sheet fromthe feeder; said conveyor being arranged to convey the sheetssuccessively through each printing couple, a sheet detector associatedwith the rotating member and movable to a first position in the presenceof a misregistered sheet and to a second position by a properlyregistered sheet, and means on the conveyor operated by said detectorwhen in the first position to actuate the registered sheet was lastpresented, and to actuate the tripping mechanism to trip "on theimpression of each of the printing couples in succession, on theapproach of a sheet carrier to which a'properly registered sheet waslast presented.

34. In a printing machine having a plurality of printing couples, asheetfeeder, a flexible path, a sheet detector in the path of sheetspresented to the sheet carriers and operable by a misregistered sheet,and means on the conveyor operated by said detector to operate thestripping device, on the approach of a sheet carrier to which amisregistered sheet was presented.

35. In a sheet registering mechanism for a printing machine, acontinuously rotating cylinder adapted to receive sheets, and means toregister a sheet received by the said cylinder, including asheetgholding device carried by the cylinder and said-holding deviceconsisting of a member acting to hold the front edge of the sheet infrontregistry and adapted to move axially of the cylinder to adjust thesheet thereon, and to act as a retarding device to resist such movementof the sheet.

36. In a sheet registering mechanism for a printing machine, acontinuously rotating cylinder adapted to receive sheets, and means toregister a sheet received by the said cylinder, including a sheetholding device carried by the cylinder, the sheet holding deviceincluding oppositely movable sheet holding members adapted to pullunequally upon the sheet held thereby to 'move it in one directionaxially on said cylinder while maintaining it taut.

37. In a printing machine having an impression cylinder, a sheet feedingdevice, a continuously rotating sheet receiving cylinder adjacent thesheet feeding device but spaced from the impression cylinder and adaptedto receive a sheet from the sheet feeding device, sheet regis teringmeans on the sheet receiving cylinder, and a sheet engaging andtransferring mechanism to remove the registered sheet from the sheetreceiving cylinder and carry it to the impression cylinder.'

' 38. In a printing'machine having an impression cylinder, 9, sheetfeeding device, a continuously rotating sheet receiving cylinderadjacent the sheet feeding device but spaced from the impressioncylinder and adapted to receive a sheet from the sheet feeding device,sheet registering means on the sheet receiving cylinder, and a sheetengaging and transferring mechanism to remove the registered sheet fromthe sheet receiving cylinder and carry it to the impression cylinder,the sheet engaging mechanism including a flexible carrier device wrappedabout the sheet receiving cylinder and directed to the impressioncylinder and having means to engage a registered sheet and transfer itfrom the sheet receiving cylinder to the impression cylinder.

39. In a sheet registering and transfer mechanism, a sheet receivingcylinder having sheet registering means thereon, and a sheet transferdevice movable with and away from the cylinder and having a sheetgripping member adapted to grip a sheet registered on the sheetreceiving cylinder and transfer it therefrom.

40. In a printing machine, a printing unit, a sheet-receiving cylinderhaving a sheet registering stop thereon and being spaced from theprinting unit, means carried by the sheet receiving cylinder to move asheet axially'thereon to position an edge of the sheet against the stop,and a sheet transferring device having'a sheet engaging member thereonto transfer a registered sheet from the sheet rec'eivingcylinder to theprinting unit.

41. In a sheet registering mechanism for a printing machine, acontinuously rotatinglcylinder adapted to receive sheets, and means toregister a sheet received by the cylinder, including a sheet holdingdevice carried by the cylinder, the sheet holding device including amember'extending longitudinally of the cylinder and acting to hold thefront edge of the sheet in front registered position and being movableaxially on the cylinder and having a series of openings therein inconnection with a source of vacuum whereby a sheet will be helddownwardly against the cylinder by atmospheric pressure and in front andside registry by said member.

42. In a sheet registering mechanism for a printing machine, acontinuously rotating cylinder adapted to receive sheets, and means toregister a sheet received by the said cylinder, including a sheetholding device carried by the cylinder, the sheet holding deviceincluding members oppositely extending and movable axially on thecylinder, each of the members having a series of openings therein inconnection with a source of vacuum, whereby a sheet will be heldagainstthe cylinder by atmospheric pressure, and means to vary the number ofopenings

